Process of improving lubricating oils



United States Patent 9 2,939,831 PROCESS or IMPROVING LIIJBRICATING on.

Joachim Lange and Gerhard Theilig, Frankfurt am Main,

Germany, and Hermann Zorn, Vienna, Austria, assignors to Farbwerke Hoechst Aktiengesellschaft vormals Meister Lucius & Briiuing, Frankfurt am Main, Germany, a corporation of Germany No Drawing. FiledOct. z, 1956, Ser. N0. 613,392 Claims priority, application Germany Oct. 17, 1955 6 Claims. (Cl. 208-28 which are insoluble in the lubricating oil and which render the latter turbid, it may be advantageous to carry -out the treatment with ethylene before the dewaxing so that these high molecular, oil-insoluble polymers can be removed simultaneously with the paraflin in the subsequent dewaxing.

The properties of the lubricating oils obtained may be improved by subsequently treating with anhydrous aluminum chloride. The aftertreatment consists of agitation with anhydrous aluminum chloride (1 to 5% and preferably 2 to 3%) at elevated temperatures from 80 to 150 C., preferably from 110 to 130 C. The treatment should last from 1 to 2 hours. After the reaction is complete, the resulting aluminum chloride sludge is removed by decantation, after cooling to room temperature, and the oil which has been freed of the sludge is neutralized by agitation with quick lime and fullers earth at elevated temperature. The aftertreatment with aluminum chloride can be carried out also by adding high-grade lubricating oils by using aluminum chloride or organoaluminum compounds. It is further known that these ethylene lubricating oil'polymers are miscible with mineral lubricating oils in any ratio and that the properties of these mixtures can be improved by an after treatment with aluminum chloride.

It has now been found that lubricating oils may be improved by treating mineral lubricating oils from any source with ethylene under pressure and at elevated temperature in the presence of free-radical initiators. The reaction of the invention is advantageously carried out at pressures from 50 to 300 atmospheres gage and at temperatures from 100F300 0, preferably between 160 C. and 250 C. V

Compounds which may be considered as free-radical initiators are peroxides, such as benzoyl peroxide, lauroyl peroxide, acetyl peroxide, diethyl peroxide, di-tert-butyl peroxide, cyclohexanone peroxide, acetone peroxide, methyl ethyl ketone peroxide, hydrogen peroxide, barium peroxide, ozone, persulfate, perborate, percarbonate, and molecular oxygen in concentrations below 0.01%; hydrazine, hydrazine salts, bibenzalazine, tnalkylamino oxides, azo compounds, such as azodinitriles, metal alkyls, such as tetraethyllead; redox systems of peroxides and pure ethylene polymers, such as are obtained according to U.S. Patent No. 2,165,372 and German Patents No. 767,929 or No. 767,128.

7 Example 1 (a) A spindle oil distillate having a specific weight of 0.898 and a viscosity of 15.78 centistokes=2.4 E at 50 C. was treated with ethylene under a pressure of e 150 atmospheres gage and at 220". C. with the addition of 1.7% by weight of di-tert-butyl peroxide. 26.2% by weight of ethylene was taken up by the spindle oil. The lubricating oil obtained was then agitated for half an hour at 150 C. with 2% quick lime and 2% fullers earth and then filtered. I

(b) The lubricating oil obtained in accordance with (a) was brought into contact with 3% by weight of aluminum chloride (anhydrous) and agitated for 2 hours at 110 C. The oil was then cooled to room temperature, allowed to stand for 8 hours, and decanted from the aluminum chloride sludge which had formed and settled. g x

The lubricating oil obtained was then agitated for half an hour with 2% quick lime and 2% fullers earth at 150 C. and then filtered. The lubricating oils obtained had the following properties:

Viscosity in Cent-lstokes at- Sp. Gr. Viscosity m-value 2 at 20 0. Index 1 20 C. 37.8 C. C. 99 0.

Original 011 0. 898 63. 25 25. 15. 78 4. 29 68 3. 39 Treated according to l-a 0. 880 86. 35 34. 46 20. 86 5. 56 107 3. Treated according to l-b 0. 878 132. 7 47. 60 28. 7.00 113 3. 63

1 Cf. Zerbe "Mlnera161e (Springer), p. 32. 1 Ct. Zerbe "Mlnera161e (Springer), p. 29.

Example 2 reducing agents, such as salts of acids of sulfur in the lower oxidation state, if necessary in the presence of amines or alcohols, or salts of metals of lower valences. The catalytic amounts are about 0.001 to 5% by weight, preferably 0.05 to 1%, of the oil to be improved.

Distillates and refined bright stock from any source may be considered as mineral lubricating oils. The treatment with ethylene can be carried out either before or after the dewaxing.

Since the treatment with ethylene may also lead to the formation of small amounts of high molecular polymers 65 The greasy reaction product was diluted with a low viscosity spindle oil in a ratio of 30:70 and freed of oilinsoluble, high polymers by filtration. The same mixture was prepared with the original bright stock (also 3. Process. of claim, 2 wherein the. lubricating rpropere 30:70). The two oils had the following properties: ties of the mineral oil are further improved by subsequent Viscosity in Centistokes at- Sp. Gr. Viscosity m-value at 20 Index 'i fntreatedbrightstoc'k and spindle f onsn:7o 0.8921 eas sass; 22.18 6.90 114 3.0a"; Treated bright stock and spindle;

Example 3 treatment of therea'ction mixture by agitation with an hydrous aluminum chloride. at. a-ternperature of about 80450 0! I v p 4. Process of claim 3 wherein the lubricant is ,cooled following the aluminum chloride treatment, the aluminum chloride sludge-is'remo'ved by "decantation, and the oil isthenneutralized.

5. Process of claim 2 wherein the ethylene-treated oil is then dewaxed, whereby-"oil-insoluble polymers formed in the ethylene treatment are removed simultaneously with' theparatfin.

6. A processforrthe preparationnof animproved lu'brzi Viscosity in Oentistokes at -Sp. Gr. Viscosity m-value at 20 C. Index 1 20 C. 37.8 C. 0. 99 C; i

(a) Original spindle oil -0. 882 27. 13. 37 8.99 3.' 01 82: (b) Spindle oil treated with CzHi.-. 0.881 65. 53 26. 00 16.02 4.82 120. 3. 71 Y (c) 50 parts of (b) +50 parts of the I I ol yethyleue.m 0.864. 199. 0 73. 20 42.80 '10. 10 I 123- 3:88" (dgMixture (c) treated with -a1u- V minum chloride v 0. 860 266. 1 93. 54 53. 12. 09 122 8.27

What we claim. and desire to protect by Letters Patent l. A process for the preparation of an improved lubricant which comprises contacting a-rnineral oil lubricant with ethylene under superatmospheric pressure and elevated. temperature inthe presence of a free-radical polymerization initiator, whereby the viscosity index and lubricating properties of the lubricant are substantially improved.

2. A process-for the preparation of an improved lubricantwhich comprises contacting a mineral lubricating oil with ethylene at a pressure of from about 50 atmospheres to about 300 atmospheres and a temperature of from about C. to about 300 C. in the presence of free-radical polymerization initiator, whereby the viscosity index and lubricating properties of the mineral oil are substantially increased.

ReferencesCited in the file ofthispatent UNITED. STATES, PATENTS Sehmerling'., Sept. 27), 19.49

2,482,877 2,560,164 -Garber-a July 10.1951, 2,566,538 Schmerling v Sept. 4, 195.1.

ronnrourarnnrs p 538,782 "Belgium Dec. 6, 1953 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent Noa 2,939,831 June 7, 1960 Joachim Lange et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the heading to the printed specification, line 9, for "Claims priority, application Germany Oct, 17, 1955" read Claims priority, application Germany Oct, 5, 1955 u Signed and sealed this 25th day of April 1961.

(SEAL) Attest:

, ERNEST We SWIDER Attesting Officer DAVID L, LADD Commissioner of Patents 

1. A PROCESS FOR THE PREPARATION OF AN IMPROVED LUBRICANT WHICH COMPRISES CONTACTING A MINERAL OIL LUBRICANT WITH ETHYLENE UNDER SUPERATMOSPHERIC PRESSURE AND ELEVATED TEMPERATURE IN THE PRESENCE OF A FREE-RADICAL POLYMERIZATION INITIATOR, WHEREBY THE VISCOSITY INDEX AND LUBRICATING PROPERTIES OF THE LUBRICANT ARE SUBSTANTIALLY IMPROVED. 